If your old rewrite rules are still in place, your URLs may work at this stage. If not, continue to install a route-based alternative: (and be sure to disable any remaining vB4 rewrite rules as they may interfere with the routes)

Follow these instructions if you wish to also change your forum directory when moving from vBulletin. A basic understanding of rewrite rules is required - these are just examples. To specify the root directory, swap out /old-dir/ or /new-dir/ for /